Lawyers for Sara Taylor delivered that message Saturday in a letter to Sen. Patrick J. Leahy, D-Vt., chairman of the Senate Judiciary Committee, which had expected to hear from Taylor Wednesday, The Times reported Sunday.

The committee issued the subpoena to Rove's former deputy as it tries to determine the role played by the White House in the firings of eight U.S. attorneys last year.

"It is unfair to Taylor that this constitutional struggle might be played out with her as the object of an unseemly tug of war," attorney W. Neil Eggleston wrote in the letter.

Taylor will refuse to testify based on a letter from White House Counsel Fred F. Fielding, "on behalf of the president directing her not to comply with the Senate's subpoena," the Times reported.

Bush has said aides must be able to give him "candid advice" without fear of being ordered to tell Congress about internal deliberations.

Democratic congressional leaders say the president's rights of executive privilege extend only to national security matters.